ftp: Use recog (fall back to regex) with the banner_version

[g0tmi1k]

This is from @cdelafuente-r7's feedback in #21380 (comment)

After

$ ./msfconsole -q -x 'db_status; workspace -D;
setg VERBOSE true; setg RHOSTS 10.0.0.10; setg LHOST tap0'
[*] Connected to msf. Connection type: postgresql.
[*] Deleted workspace: default
[*] Recreated the default workspace
VERBOSE => true
RHOSTS => 10.0.0.10
LHOST => tap0
msf > use ftp_anonymous

Matching Modules
================

   #  Name                                 Disclosure Date  Rank    Check  Description
   -  ----                                 ---------------  ----    -----  -----------
   0  auxiliary/scanner/ftp/ftp_anonymous  .                normal  No     Anonymous FTP Access Detection


Interact with a module by name or index. For example info 0, use 0 or use auxiliary/scanner/ftp/ftp_anonymous

[*] Using auxiliary/scanner/ftp/ftp_anonymous
msf auxiliary(scanner/ftp/ftp_anonymous) > run
[*] 10.0.0.10:21          - Testing write access, creating test directory: fzgzOlMG
[+] 10.0.0.10:21          - Anonymous Read-only access (vsFTPd 2.3.4)
[*] 10.0.0.10:21          - Listing directory contents
[*] 10.0.0.10:21          - Directory listing: (empty)
[*] 10.0.0.10:21          - Scanned 1 of 1 hosts (100% complete)
[*] Auxiliary module execution completed
msf auxiliary(scanner/ftp/ftp_anonymous) >

---

Proof

$ git diff ./lib/msf/core/exploit/remote/ftp.rb
diff --git a/lib/msf/core/exploit/remote/ftp.rb b/lib/msf/core/exploit/remote/ftp.rb
index a2a8855f6d..15a2ca2da9 100644
--- a/lib/msf/core/exploit/remote/ftp.rb
+++ b/lib/msf/core/exploit/remote/ftp.rb
@@ -119,7 +119,7 @@ module Exploit::Remote::Ftp
   #
   def banner_version
    info = recog_banner
-   return [info['service.product'], info['service.version']].compact.join(' ') if info
+   return [info['service.product'], info['service.product'], info['service.version']].compact.join(' ') if info

     # 220 (vsFTPd 2.3.4)\x0d\x0a                                   -> vsFTPd 2.3.4
     # 220 ProFTPD 1.3.1 Server (Debian) [::ffff:10.0.0.10]\x0d\x0a -> ProFTPD 1.3.1 Server (Debian)
$ ./msfconsole -q -x 'db_status; workspace -D;
setg VERBOSE true; setg RHOSTS 10.0.0.10; setg LHOST tap0; use ftp_anonymous; run'
[...]
[+] 10.0.0.10:21          - Anonymous Read-only access (vsFTPd vsFTPd 2.3.4)
[...]
msf auxiliary(scanner/ftp/ftp_anonymous) >

[g0tmi1k]

Thanks for the feedback @adfoster-r7 - Forced pushed with changes.